MADISON, Wis. — Former Wisconsin Gov. Tommy Thompson has won the Republican nomination for a U.S. Senate seat the party is trying to capture for the first time in more than five decades.

The ex-governor and Health and Human Services secretary under President George W. Bush defeated three GOP rivals during Tuesday's primary.

It marked Thompson's first time on the ballot since 1998. He advances to face Democrat Tammy Baldwin in the Nov. 6 election.

The seat became open following the retirement of Democrat Herb Kohl.

The win follows a blistering primary in which hedge fund investor Eric Hovde invested nearly $5 million of his own money into the race. U.S. Rep. Mark Neumann and state Assembly Speaker Jeff Fitzgerald also sought the GOP nomination.